There are known various types of non-contact cutting apparatus for cutting sheet metal work pieces. When, for example, a laser cutter is used to make holes in a work piece, by cutting along a closed or continuous path, cutouts or slugs result. In certain cases, such as, when the work piece is a partially assembled product, it may be required that the slugs be collected and not permitted to fall into the work area.
A particular situation when the work piece is a partially assembled product is when the work piece is a car body. Once the body only has been assembled, (a situation known in the car industry as `body in white`). apertures are formed in it so as to permit assembly of various fixtures. It will be appreciated that it is most undesirable for the slugs resulting from the apertures formed in the car body to fall inside it. Manual removal of these slugs is, however, time-consuming and adds, therefore, to the production cost of cars.
A cutting head employing a permanent magnet and a selectably operable system high pressure air jets is known, wherein a slug, formed as described above, is attracted to the magnet so as to become retained thereby. Once the cutting head has been moved to a predetermined location, the air jets are operated so as to overcome the retentive force of the magnet, causing separation of the slug therefrom and removal of the slug from the cutting head.
This system of air jets, however, has been found not to be entirely reliable, as it does not always remove the slugs from the cutting head, and slugs, therefore, may remain attached to the permanent magnet so as to interfere with subsequent cutting operations.